Drilling machine



G. H, GlLMAN 1,982,656

DRILI'TNG MACHINE Filed Dec. 51, 1930 2 Sheets-Shea?l l Dec. 4, 1934.

I N VEN TOR A TTORNE Y GEORGE: H.G|LmnN.

Dec. 4, 1934. G. H. GsLMAN Y 1,982,656 t DRILLING MACHINE Filed Dec. 3l, i930 2 Sheets-Shea?l 2 ATTORNEY l NTOR lBY 170V Patented Dec. 4, 1934 UNITED STAT-Es PATENT oF'FicE DRILLING MACHINE Application'oecember 31, 1930, serialfNo. 505,810

7 Claims.

Thisfinvention relates to A drilling machines comprising a pressure-fluid operated reciprocatinghammer-piston for imparting a driving blow to a drillsteel or barandfluid pressure actuated 6 means 'for rotating the drill bar.

object of the presentinvention is to provide a Idrilling machine as specified, embodying a simple form of rinterrupted flow type valve which maybe produced for a minimum ofexpense and l ywhich `is adaptedl tol be quickly and positively thrown and maintained in its operative positions forsinsuring-an'irnmediate and abundant supply ofvpressure fluid lto the ends of the cylinder for actuating the hammer-piston.

Also, to provide adrilling. machine in which the above operating result is insured by meansfor admitting to thefront of the cylinder chamber, independent/of the valve, an ample supply of pressure'fluid to `initiate they returnV of thehammer- .20 -pistorion its stroke immediately it 'delivers its blowupon the drill steel or bar, and this supply of pressureiiuid to the cylinder serves also to quickly-throw the-valve to its forward limit of traveland subsequently to maintain it in this position during-the time the piston is making its rearward stroke.

"With theseand Aother objects in view, as may appearfrom `the accompanying specification, the invention consists of various features of construction-and` combination of parts, which will be first described "in connection with the accompanying drawings, showing a drilling machine of the preferred form embodying the invention, and the .features formingvthe invention will be specifically pointed out in the claims.

y In" theV drawings y Si Figl Ais-alongitudinal section through a drilling machine embodying the present invention.

v2 `is a-'diagrammatic longitudinallsection v440 through the'drillingmachine showing the hammer pistontowards-theforward end ofthe cylin- -der and showing `the valve in position for delivering-pressure fluid to the forward end of the cylinder.'

@.45 l@ Fig. =3 is adiagrammaticlongitudinal section similar to Fig. .2", only showing the hammer piston at "their-ear end of the cylinder and the valve inposition-for-'delivering fluid to the rear end of Athe cylinder. 5o Fig.. 4 is a planv-iew of the valveembodied in fthefdrilling machine.

"'Fig; 5 isan edge elevation of the valve.

if .'Fig.-`16 is a side elevation of the valve.

1- lllteferring' i more i particularly to v the drawings 1..55 Vthe improved Edrill-ing machine `is ofvv the type particularly, but not exclusively, provided for drilling rock, coal or like formations and it comprises the cylinder body l in which a hammer piston 2 reciprocates. The hammer piston 2comprises a piston proper 3 and the hammer extension 4 60 which engages the drill steel or drill bar 5 for transmitting a sharp decisive blow to the end of the drill steel 5 for driving it forward into ythe formation being drilled. In 'the present type of drilling machine, the drill bar or drill steel 5 is rotated through the medium of a chuck 6 and a rotating pressure uid operated motor '7 of approved type and similar to that disclosed in my prior Patent 1,605,712.

The admission of pressure fluid into the drilling machine is controlled by the throttle 8 and its distribution is in turn controlled by the valve 9. This valve 9, specifically/,illustrated in Figs. 4, 5 and 6 is substantially in the shape of a horseshoe being constructed from a flat piece of ma- 5' terial and having a portion thereof cut away, as shown at 10, to permit unimpeded movement of thevalve and at the same time allow the connection of the flushing fluid conduits 10 such as a water tube of the type commonly used in rock drills with their proper associate parts in the drilling machine organism.

The cylinder 1 has a forward cylinder extension llimounted therein, which is provided with a plurality of pressure fluid'distributing pas- 5 sageways which are diagrammatically yillustrated in Figs. 2 and 3 of the drawings and Will be more specifically referred to hereinafter. y

In operation, when the throttlev valve 8 is first opened with the piston 2 in the position, as shown 0 in Fig. 3 of the drawings, the pressure fluid passes through the passageway 20, past-the valve 9 and into the cylinder 1 behind the piston 3 of the hammer-piston structure, and drives the hammer-piston forward to impart a driving blow to the-drill steel 5. At the same time the `pressure fluid passes on through the passage 20 into the annular motor inlet supply groove 22 formed in the cylinder extension 11. From the groove 22 the pressure fluid passes through the motor inlet ducts 23 to the motor structure 7 and imparts a rotary movement to the drill steel 5, at the proper interval, through the medium of the chuck 6 and reduction gearing 14. f

In the diagrammatic Figure 2 with the `hammer-piston in the position shown, it is assumed that the hammer blow has just been delivered on the shank end of the drill steel 5 and it will be noted that pressure fluid or live air at hose line pressure is conducted from the throttle valve 8 to each, the mouth 20' of the valve chamber 24, to the motor supply inlet groove 22 and through the radial ducts 25 to the rearward annular groove 26 of the front cylinder extension l1 in which the hammer bar extension 4 of the piston structure 2 reciprocates.

Immediately prior to the delivery of the blow by the hammer-piston on the shank end of the drill steel, the rear edge of the piston head 3, when on its forward stroke, partially uncovers the exhaust port 27 leading from the cylinder l` to the atmosphere, thus allowing the pressure uid from the rear cylinder 'chamber to be exhausted.

Immediately thereafter, the forward edge of the annular groove 28 on the hammer bar extension 4 enters the live air groove 26, thus causing live pressure fluid or air to be conducted from the groove 26 to the front cylinder chamber 1A, where it serves the dual function of acting upon the front face of the piston head 3 to initiate its return stroke and by virtue of the supplementary return port 29 the pressure fluid returns to the valve chamber 24 and serves to throw the valve 9 to its forward seat or in the position, as shown in Fig. 2. When the valve 9 is in its forward position communication is established between the throttle valve 8 and the forward cylinder chamber 1A by way of the supplemental return port 29, which permits the pressure uid or live air at hose line pressure to be conducted into the forward cylinder chamber 1A for acting upon the forward face of the piston head 3 and forcing it rearwardly into the rear end of the cylinder l and into the position, as shown in Fig. 3 of the drawings. During the rearward travel of the hammer-piston structure 2 the head 3 uncovers the forward edge of the exhaust passage 27, at which time the entire volume of air from the fr ont cylinder chamber 1A is exhausted to the atmosphere.

When the hammer-piston 2 has moved rearwardly a distance sufficiently t0 move the annular groove 28 in the hammer extension beyond or rearwardly of the groove 26 the supplemental supply of pressure fluid to the valve chamber 24 is cut 01T and the piston in its rearward movement builds up suiicient pressure in the rearward piston chamber 1B to throw the valve 9 to its rearward seat or into the position, as shown in Fig. 3 of the drawings, at which time the pressure fluid or live air at hose line pressure is` admitted from the throttle 8 into the rear piston chamber 1B behind the piston head 3 to force the hammer-piston forwardly.

The cylinder 1 is provided with a supplemental expansion chamber 31 into which a supply of pressure fluid is trapped and compressed by the cylinder extension 32, during the rearward travel of the hammer-piston 2, and when the valve 9 is thrown to its rearward position this entrapped compressed pressure fluid acts to give an initiative stroke to the hammer-piston.

When the hammer-piston has again moved forward to the extent that the rear edge of the piston head 3 uncovers the exhaust passage, the air or pressure uid in the rearward end or chamber 1B of the cylinder and the pressure fluid entrapped in the extension 31 is exhausted to the atmosphere and a hammer blowis delivered upon the shank end of the drill steel 5, thus completing the cycle of operation.

The pressure fluid which serves to operate the motor 7 and rotate the drill steel 5 exhausts through suitable passages 34, the annular passage 35 and the port 36, which opens to atmosphere.

In the diagrammatic Figures 2 and 3 an intermittent throttle controlled blow port 37 is illustrated by means of which pressure fluid may be delivered to the chamber 38 from which it is utilized for blowing out the drill hole.

It will be understood that the invention is not to be limited to the specic construction or arrangement of parts shown but that they may be widely modified within the invention dened by the claims.

What is claimed is:

1. In a drilling machine, a cylinder having a bore and an exhaust port therein, a hammer piston reciprocably mounted in said cylinder bore, said cylinder provided with a port opening into the cylinder -bore behind; said piston and into the cylinder bore in front of the piston, a valve interposed in said port for controlling passage of pressure iiuid into the cylinder alternately behind and in front of the piston, said cylinder provided with a constant pressure supply port for delivering pressure fluid to the cylinder in front of said piston, said last named port controlled by said hammer piston, the part of said iirst named port opening into the cylinder in front of the piston forming a supplementary return port for leading pressure iiuid to the valve to move the valve to cut oi passage of pressure-huid to the cylinder behind the piston.

2. In a drilling machine, a cylinder having a bore and an exhaust port therein, a hammer piston reciprocably mounted in said bore, said cylinder provided with a port opening into the cylinder bore behind said piston and into the cylinder bore in front of the piston, said cylinder provided with a valve receiving recess extending across said bore and having one of its sides disposed at an acute angle to the other side, a flat loosely seated valve in said recess and limited in its movement by the sides of the recess, said valve controlling the passage of pressure fluid into the cylinder alternately behind and in front of the piston, said cylinder provided with a constant pressure supply port for delivering pressure fluid tothe cylinder in front of said piston, said lastl named port being controlled by said hammer piston, the part of said rst named port opening into the cylinder in front of the piston forming a supplementary return port for leading pressure uid to the valve to move the valve to cut off passage of pressureiiuid to the cylinder behind the piston.

3. In a drilling machine, a cylinder having an exhaust port therein, a hammer-piston reciprocably mounted in the cylinder, a valve chamber, a valve therein, said cylinder being provided with means for admitting pressure-fluid in front of the piston during its forward stroke and to said valve chamber, ports controlled by said valve for supplying pressure-fluid from said valve chamber to said cylinder one in front and one behind said hammer-piston, the port opening in front of said hammer-piston forming a supplemental return port and conveying pressure-fluid delivered to said cylinder by said means to said chamber for reversing the valve upon the relief of pressure in front of the valve through said exhaust port and cutting off flow of piston operating pressureuid behind said hammer-piston.

4. In a drilling machine, a cylinder having an exhaust port therein, a hammer-piston reciprocably mounted in the cylinder, a valve chamber, a valve therein, said cylinder being provided with means for admitting pressure-uid in front of the piston during its forward stroke and to said valve chamber, ports controlled by said valve for supplying pressure-fluid from said valve chamber to said cylinder one in front and one behind said hammer-piston, the port opening in front of said hammer-piston forming a supplemental return port and conveying pressure-fluid delivered to said cylinder by said means to said chamber for reversing the valve upon the relief of pressure in front of the valve through said exhaust port and cutting off flow of piston operating pressure-fluid behind said hammer-piston, said cylinder provided with a supplemental recess at its rear end, an extension on the rear end of said hammerpiston for cooperating with said supplemental recess to compress pressure-fluid therein for imparting an initiative forward movement to the hammer-piston. i

5. In a drilling machine, a cylinder having an exhaust port therein, a hammer-piston reciprocably mounted in the cylinder, a valvechamber, a substantially horse-shoe shaped floating valve mounted in said chamber, said cylinder being provided with means for admitting pressure-huid in front of the piston during its forward stroke and to said valve chamber, ports controlled by said valve for supplying pressure-huid from said valve chamber to said cylinder one in front and one behind said hammer-piston, the port opening in front of said hammer-piston forming a supplemental return port and conveying pressure-fluid delivered to said cylinder by said means to said chamber for reversing the valve upon the relief of pressure in front of the valve through said exhaust port and cutting 01T flow of piston operating pressure-Huid behind said hammer-piston.

6. In a drilling machine, a cylinder having an exhaust port therein, a hammer-piston reciprocably mounted in the cylinder, a valve chamber, a substantially horse-shoe shaped floating valve mounted in said chamber, said cylinder being provided with means for admitting pressure-fluid in front of the piston during its forward stroke and to said valve chamber, ports controlled by said valve for supplying pressure-fluid from said valve chamber to said cylinder one in front and one behind said hammer-piston, the port opening in front of said hammer-piston forming a supplemental return port and conveying pressure-fluid delivered to said cylinder by said means to said chamber for reversing the valve upon the relief of pressure in front of the valve through said exhaust port and cutting ofl flow of piston operating pressure-fluid behind said hammer-piston, said valve being moved to open the rear end of the chamber to piston operating pressure-huid by force of pressure built up within the cylinder during rearward movement of the piston.

7. In a drilling machine, a cylinder having an exhaust port therein, a hammer-piston reciprocably mounted in the cylinder, a valve chamber, a substantially horse-shoe shaped floating valve mounted in said chamber, said cylinder being provided with means for admitting pressure-fluid in front of the piston during its forward stroke and to said valve chamber, ports controlled by said valve for supplying pressure-fluid from said valve chamber to said cylinder one in front and one behind said hammer-piston, the port opening in front of said hammer-piston forming a supplemental return port and yconveying pressurefluid delivered to said cylinder by said means to said chamber for reversing the valve upon the relief of pressure in front of the valve through said exhaust port and cutting off flow of piston operating pressure-fluid behind said hammerpiston, said valve being moved to open the rear end of the chamber to piston operating pressureiiuid by force of pressure built up within the cylinder during rearward movement of the piston, said hammer-piston normally cutting off communication between said means and the supplemental return port, and said hammer-piston being provided with a cut away portion adapted to open said means to said supplemental return port at a predetermined time during movement of said hammer-piston.

GEORGE H. GILMAN. 

